1. Field of the Invention
The present invention relates to an image processing device, a singular spot detection method, and a recording medium upon which a singular spot detection program is recorded, which, using a distance image, perform the detection of singular spots which is necessary when a robot or a vehicle moves.
2. Description of Related Art
For an autonomous robot or a self propelled vehicle to perform movement safely, it is necessary to detect special environmental structures such as intersections or descending steps or the like. In order to do this, a radar unit or the like is often provided to the robot or vehicle, and movement control is then performed from information about the surrounding environment which is obtained by this radar unit. However, if self-control of movement is to be performed from the detected information, it is necessary to ensure that the detected information is correct and does not include any unnecessary information.
However, since the surrounding environment when a robot or a vehicle moves is complicated, the processing for only extracting information which is accurate and also applicable becomes extremely complicated, and the problem arises that it is necessary to provide several means for detecting the surrounding environment.
The present invention has been conceived in view of this sort of circumstance, and its objective is to propose an image processing device, a singular spot detection method, and a recording medium upon which a singular spot detection program is recorded, which can perform the detection of singular spots which is required for movement control when a robot or vehicle moves autonomously.
The invention of the first aspect comprises: a distance image capture device (for example, the distance image capture section 1 of the embodiment) which captures a distance image based upon three dimensional coordinate values obtained for various points upon object surfaces by measuring the distances to the points upon the object surfaces in the forward visual field of a distance sensor; a plane detection device (for example, the plane detection section 3 of the embodiment) which detects planes from the three dimensional coordinate values upon the object surfaces obtained from the distance image; an edge detection device (for example, the edge detection section 4 of the embodiment) which detects edges from the distance image; a singular spot decision device (for example, the singular spot decision section 5 of the embodiment) which decides whether or not the edges include singular spots, according to whether or not the edges which have been detected by the edge detection device and the planes which have been detected by the plane detection device satisfy predetermined conditions; and a singular spot map storage device (for example, the singular spot map storage section 7 of the embodiment) which stores the singular spots, based upon the results from the singular spot decision device.
According to the invention of the first aspect, since edge detection processing is performed upon the distance image and sudden changes of distance are detected, thereby it becomes possible to detect singular spots such as intersections or descending steps or the like at high speed. Further, it becomes possible to enhance the accuracy of detection of singular spots, since the spots on these edges are taken as singular spots only when the edges which have been detected by the edge detection and the planes which have been detected by the plane detection satisfy predetermined conditions. Yet further, since it is arranged that the edge detection and the plane detection are processed in parallel, thereby the benefit is obtained that it is possible to enhance the speed of detection processing for the singular spots.
The invention of the second aspect is a vehicle movement control device comprising an image processing device according to the first aspect, wherein the vehicle movement control device comprises a movement control device (for example, the movement control section 8 of the embodiment) which, during vehicle movement, performs movement control by referring to the singular spot map.
According to the invention of the second aspect, since it is arranged that the movement of the vehicle is controlled while referring to the singular spot map, thereby, along with it being possible to perform control of the position of the vehicle with good accuracy, the advantage is obtained that it becomes possible to control the generation of the movements necessary when approaching a singular spot.
The invention of the third aspect is an autonomously moving robot comprising an image processing device according to the first aspect, wherein the autonomously moving robot comprises a movement control device (for example, the movement control device 8 of the embodiment) which, during robot movement, performs movement control by referring to the singular spot map.
According to the invention of the third aspect, since it is arranged that the movement of the robot is controlled while referring to the singular spot map, thereby, along with it being possible to perform control of the position of the robot with good accuracy, the advantage is obtained that it becomes possible to control the generation of the movements necessary when approaching a singular spot.
The invention of the fourth aspect comprises: distance image capture processing which captures a distance image based upon three dimensional coordinate values obtained for various points upon object surfaces by measuring the distances to the points upon the object surfaces in the forward visual field of a distance sensor; plane detection processing (for example, the step S1 of the embodiment) which detects planes from the three dimensional coordinate values upon the object surfaces obtained from the distance image; edge detection processing (for example, the step S2 of the embodiment) which detects edges from the distance image; and singular spot decision processing (for example, the step S5 of the embodiment) which decides whether or not the edges include singular spots, according to whether or not the edges which have been detected by the edge detection device and the planes which have been detected by the plane detection device satisfy predetermined conditions.
According to the invention of the fourth aspect, since edge detection processing is performed upon the distance image and sudden changes of distance are detected, thereby it becomes possible to detect singular spots such as intersections or descending steps or the like at high speed. Further, it becomes possible to enhance the accuracy of detection of singular spots, since the spots on these edges are taken as singular spots only when the edges which have been detected by the edge detection and the planes which have been detected by the plane detection satisfy predetermined conditions. Yet further, since it is arranged that the edge detection and the plane detection are processed in parallel, thereby the benefit is obtained that it is possible to enhance the speed of detection processing for the singular spots.
The invention of the fifth aspect is a recording medium which can be read by a computer, upon which is recorded a singular spot detection program which detects singular spots in a forward visual field, wherein the singular spot detection program causes the computer to perform: distance image capture processing which captures a distance image based upon three dimensional coordinate values obtained for various points upon object surfaces by measuring the distances to the points upon the object surfaces in the forward visual field of a distance sensor; plane detection processing (for example, the step S1 of the embodiment) which detects planes from the three dimensional coordinate values upon the object surfaces obtained from the distance image; edge detection processing (for example, the step S2 of the embodiment) which detects edges from the distance image; and singular spot decision processing (for example, the step S5 of the embodiment) which decides whether or not the edges include singular spots, according to whether or not the edges which have been detected by the edge detection device and the planes which have been detected by the plane detection device satisfy predetermined conditions.
According to the invention of the fifth aspect, since edge detection processing is performed upon the distance image and sudden changes of distance are detected, thereby it becomes possible to detect singular spots such as intersections or descending steps or the like at high speed. Further, it becomes possible to enhance the accuracy of detection of singular spots, since the spots on these edges are taken as singular spots only when the edges which have been detected by the edge detection and the planes which have been detected by the plane detection satisfy predetermined conditions. Yet further, since it is arranged that the edge detection and the plane detection are processed in parallel, thereby the benefit is obtained that it is possible to enhance the speed of detection processing for the singular spots.